It is well known in the art to utilize various arrangements for equilibrating a weapon system that includes a set of parts pivoted about a trunnion as the elevation of the weapon is adjusted. Such known arrangements rely upon pneumatic, hydraulic and spring mechanisms to achieve equilibration.
In addition to equilibration, it is desirable to stabilize the weapon as it is fired. Some of the present stabilizing arrangements use a large hydraulic cylinder whose servo control may create hydraulic pressures of several thousand pounds per square inch (psi) during equilibration. These systems, in addition to the pressure exerted to equilibrate the weight on the gun muzzle, must withstand recoiled forces of fifty thousand pounds, dissipated within less than 0.5 seconds, as the gun fires. This dynamic increase in force exerted upon the noncompressable hydraulic fluid can generate pressures up to 8,000 psi. These high pressures require the design of extremely rugged hydraulic systems in order to prevent the rupture of pipe fittings, joints and valves.
The reader's attention is directed to three patents, cited as examples of prior art systems using pneumatic, hydraulic or spring equilibrator assemblies. A pneumatic system may be found in U.S. Pat. No. 3,562,901, which issued on Feb. 16, 1971, by Joseph Ray. A hydraulic system may be found in U.S. Pat. No. 4,402,252, which issued on Sept. 6, 1983, by Walter Klumpp. Lastly, a spring system may be found in U.S. Pat. No. 4,040,332, which issued on Aug. 9, 1977, by Robert O. Border, et al.
While these systems address the problem of equilibrating the weight of a gun nozzle or countering its recoil force, each system suffers from its own limitation. The hydraulic equilibration system is subject to failure upon firing due to sharply increased hydraulic pressure. Spring and pneumatic systems suffer from design limitations. Some designs may be optimized around equilibration, while others are optimized around counterbalancing the recoil forces. It is difficult to design a system optimized to solve each problem.
It is an object of the present invention to provide a mechanical spring system capable of equilibrating a gun system and of absorbing the dynamic forces generated by its recoil.
Another object of the present invention is to provide an equilibrator assembly which may be easily designed to counterbalance the forces generated by the weight of a gun muzzle as it is elevated and depressed.
A further object of the present invention provides an equilibrator assembly which requires relatively low drive forces to adjust the assembly.
A still further object is to establish an equilibrator assembly driven by a lead screw which automatically locks the gun at any elevation, even after experiencing the dynamic forces of a firing recoil.
Yet a further object of the invention provides an equilibrator assembly for absorbing the recoil forces without transmitting those forces to the drive mechanism of the assembly.